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arXiv · 1411.3760

Simulating tidal streams in a high resolution dark matter halo

Wayne Ngan·Brandon Bozek·Raymond G. Carlberg·Rosemary F. G. Wyse·Alexander S. Szalay·Piero Madau
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Abstract

We simulate tidal streams in the presence and absence of substructures inside the zero redshift snapshot of the Via Lactea II (VL-2) simulation. A halo finder is used to remove and isolate the subhalos found inside the high resolution dark matter halo of VL-2, and the potentials for both the main halo and all the subhalos are constructed individually using the self-consistent field (SCF) method. This allows us to make direct comparison of tidal streams between a smooth halo and a lumpy halo without assuming idealized profiles or triaxial fits. We simulate the kinematics of a star cluster starting with the same orbital position but two different velocities. Although these two orbits are only moderately eccentric and have similar apo- and pericentric distances, we find that the two streams have very different morphologies. We conclude that our model of the potential of VL-2 can provide insights about tidal streams that have not been explored by previous studies using idealized or axisymmetric models.

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Wayne Ngan, Brandon Bozek, Raymond G. Carlberg, Rosemary F. G. Wyse, Alexander S. Szalay, Piero Madau. 2015-04-20. Simulating tidal streams in a high resolution dark matter halo. https://doi.org/10.1088/0004-637x%2F803%2F2%2F75

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